sealed class MyClass {
    class ValueA() : MyClass()
    data class ValueB(val name: String = "Name_B") : MyClass()
    data class ValueC(val title: String = "Name_C", val ordinal: Int = 0) : MyClass()
}

fun myFunc(arg: MyClass): String = when(arg) {
    is MyClass.ValueA -> "A"
    is MyClass.ValueB -> "B: ${arg.name}"
    is MyClass.ValueC -> "C: ${arg.title}, ${arg.ordinal}"
}

fun main(args: Array<String>) {
    val T = MyClass.ValueC()
    println(myFunc(T))
}